The problem of enabling safe footing on slippery surfaces has engaged the attention of numerous prior inventors. Most prior inventors have used metal spikes protruding downward, using various kinds of attachment devices. Most of the devices in the prior art were devised in the age of laminated leather heels. Some, such as those shown in U.S. Pat. Nos. 628,263 and 2,034,050 required permanent attachment of appendages to the heels of the shoes or boots to enable installation; others, such as those shown in U.S. Pat. Nos. 628,263; 946,543 and 344,666 utilized clamps or straps completely or partially encircling the heel; and still others, such as U.S. Pat. Nos. 761,915 and 2,499,516 provided attachment across the instep. Finally, U.S. Pat. Nos. 607,686 and 908,040 show clamps combined with screw-type attachment to the wearer's heel.
None of the prior art shows a simple, light-weight method of attachment to modern heels of synthetic material.